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                                                Background
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                                                IgM is found in normal plasma at a concentration of 1.2 to 4.0 mg/mL. It is the first immunoglobulin produced during the immune response, the first antibody in neonates, and is involved in pathogenesis of autoimmune diseases. A diminished level of IgM is associated with Wiskott-Aldrich syndrome.   Synonyms: Immunoglobulin M Kappa Protein, Human IgM kappa, Human IgMk Protein.
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